Each non-abstract Model class must have a
Manager instance added to it.
Django ensures that in your model class you have at least a
default Manager specified. If you don’t add your own Manager,
Django will add an attribute objects containing default
Manager instance. If you add your own
Manager instance attribute, the default one does
not appear. Consider the following example:

fromdjango.dbimportmodelsclassPerson(models.Model):# Add manager with another namepeople=models.Manager()